As is well known and understood, stethoscopes are used extensively in medical practice to allow a physician or other provider of medical care to monitor sounds in the respiratory, cardiac, plural, arterial, venus, and other body systems. As is also well known and understood, it is typical for physicians and other care providers to employ this highly used medical instrument from patient to patient, either by constantly having it upon their person, or near at hand, while in the treating environment. (For example, and when carried about, it is not unusual to find the physician or provider of medical care to employ the stethoscope on between 15-20 patients per hour in a hospital environment, and anywhere between 6 and 12 patients in an office setting.) As the acceptable practice, the diaphragm of the stethoscope in such usage is placed directly on the skin of the patients--and, as a result, the entire stethoscope diaphragm thus becomes susceptible to contamination and to the passing of such contamination from patient to patient unless the diaphragm is sterilized between each use. However, as such process is extremely time consuming, a sterilization of the stethoscope diaphragm is not common, even if there existed--which there does not--any recommended procedure for the sterilization of the stethoscope diaphragm.
As is also well appreciated, such danger of contamination being transferred is magnified when used in neo-natal care, where the newborns are most at risk to the transfer of communicable diseases, colds, or other contaminants. Since a stethoscope is often placed at points where such body fluids and contaminants as blood, urine, tears, exist, it becomes even more important that the stethoscope diaphragm either be sterilized between uses, or be shielded in use so as to limit the opportunity for such fluids and contaminants to reach the stethoscope diaphragm itself.
It is also desirable to protect both the patient and the physician from contacting each other near the stethoscope diaphragm in order to prevent the transfer of body fluids and other contaminants between the patient and the physician.